Re: [PATCH 10/10] xfs_admin: support adding features to V5 filesystems

From: Brian Foster <bfoster@redhat.com>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: sandeen@sandeen.net, linux-xfs@vger.kernel.org
Subject: Re: [PATCH 10/10] xfs_admin: support adding features to V5 filesystems
Date: Tue, 9 Feb 2021 12:22:04 -0500	[thread overview]
Message-ID: <20210209172204.GH14273@bfoster> (raw)
In-Reply-To: <161284386088.3057868.16559496991921219277.stgit@magnolia>

On Mon, Feb 08, 2021 at 08:11:00PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
> 
> Teach the xfs_admin script how to add features to V5 filesystems.
> 
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---
>  db/xfs_admin.sh      |    6 ++++--
>  man/man8/xfs_admin.8 |   22 ++++++++++++++++++++++
>  2 files changed, 26 insertions(+), 2 deletions(-)
> 
> 
> diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
> index 430872ef..7a467dbe 100755
> --- a/db/xfs_admin.sh
> +++ b/db/xfs_admin.sh
> @@ -8,9 +8,10 @@ status=0
>  DB_OPTS=""
>  REPAIR_OPTS=""
>  REPAIR_DEV_OPTS=""
> -USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-r rtdev] [-U uuid] device [logdev]"
> +DB_LOG_OPTS=""
> +USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-O v5_feature] [-r rtdev] [-U uuid] device [logdev]"

Technically this would pass through the lazy counter variant on a v4
super, right? I wonder if we should just call it "[-O feature]" here.

>  
> -while getopts "c:efjlL:pr:uU:V" c
> +while getopts "c:efjlL:O:pr:uU:V" c
>  do
>  	case $c in
>  	c)	REPAIR_OPTS=$REPAIR_OPTS" -c lazycount="$OPTARG;;
...
> diff --git a/man/man8/xfs_admin.8 b/man/man8/xfs_admin.8
> index cccbb224..3f3aeea8 100644
> --- a/man/man8/xfs_admin.8
> +++ b/man/man8/xfs_admin.8
...
> @@ -106,6 +108,26 @@ The filesystem label can be cleared using the special "\c
>  " value for
>  .IR label .
>  .TP
> +.BI \-O " feature1" = "status" , "feature2" = "status..."
> +Add or remove features on an existing a V5 filesystem.

s/existing a/existing/

Also, similar question around the lazycount variant. If it works, should
it not be documented here?

Brian

> +The features should be specified as a comma-separated list.
> +.I status
> +should be either 0 to disable the feature or 1 to enable the feature.
> +Note, however, that most features cannot be disabled.
> +.IP
> +.B NOTE:
> +Administrators must ensure the filesystem is clean by running
> +.B xfs_repair -n
> +to inspect the filesystem before performing the upgrade.
> +If corruption is found, recovery procedures (e.g. reformat followed by
> +restoration from backup; or running
> +.B xfs_repair
> +without the
> +.BR -n )
> +must be followed to clean the filesystem.
> +.IP
> +There are currently no feature options.
> +.TP
>  .BI \-U " uuid"
>  Set the UUID of the filesystem to
>  .IR uuid .
> 